What Does Reverse Osmosis Remove?

The drinking water we drink is full of minerals that can pose a risk to our health. Therefore, before choosing a RO to filter, it is essential to know “what does reverse osmosis remove.”

These molecules are more physically large than water molecules, so removing them using the RO filtration five-stage process is easy.

The premium reverse osmosis device can remove up to 99.99 percent of harmful substances from the water supply. 

The issue is whether eliminating the minerals essential to our body’s proper function is healthy for us. Let’s find out.

What is Reverse Osmosis System?

Reverse Osmosis is the water filtration system that employs a semi permeable, thin membrane with tiny pores that let clean water in a while, excluding larger molecules, such as dissolved salts ionized along with other impurities.

Reverse Osmosis produces highly pure water used in industrial boilers and drinking water systems, sal twater treatment, pharmaceutical manufacturing, cosmetics production, food and beverages, and many other uses.

How Does Reverse Osmosis Work?

In Reverse Osmosis, the applied pressure is utilized to beat the pressure of Osmosis and feed water from high levels of contaminants to a lower concentration of contaminants. 

It’s because it’s forced into reverse, and the contaminated water is trying to flow into pure water.

However, because it needs to go through an initial water filter so that the contaminants remain and only pure water flows through, this results in clean drinking water as we need!

Reverse Osmosis generally comprises four phases of filtration to remove contaminants, including the sediment filter, pre-carbon block, reverse osmosis membrane, and post-carbon filters.

The sediment filter removes the most massive particles, such as dirt, sand, and corrosion, to keep them from other filters.

The pre-carbon water filter uses activated carbon to stop anything bigger than a small amount of flour from entering the filter and help to reduce unwanted smells like Bleach and Chlorine.

And also binding and attracting positively charged ions to block chemical compounds, such chloramines, and chlorine, from getting through to the next filter.

The reverse osmosis membrane eliminates heavier molecules than water, like sodium, and the high concentrations of lead and dissolved minerals, and fluoride.

The post-carbon filters polish the water and perfect the RO system for the Apartment.

What Does Reverse Osmosis System Remove From Drinking Water?

The reverse osmosis procedure makes use of a semipermeable membrane for the removal of various contaminants.

Here is a brief list of the impurities eliminated from the water by RO.

Ions and metalsOrganic chemicalsPesticidesParticles
85 – 95% PotassiumCarbon tetrachloride*LindaneAsbestos
94 – 98% MagnesiumBenzene*EndrinProtozoan cysts
94 – 98% CalciumDichlorobenzene*PentachlorophenolCryptosporidium
94 – 98% IronToluene*1,2,4-trichlorobenzene*
94 – 96% SeleniumTrihalomethanes*2,4-D*
92 – 96% ArsenicTrichloroethylene*Atrazine*
95 – 98% MercuryHeptachlor
85 – 94% Sodium
95 – 98% Zinc
95 – 98% Lead
85 – 92% Chloride
94 – 98% Manganese
96 – 98% Nickel
95 – 98% Cadmium
95 – 98% Barium
60 – 75% Nitrate
96 – 98% Sulfate
96 – 98% Phosphate
84 – 92% Cyanide
85 – 92% Fluoride

*The only way to get rid of these contaminants is to ensure your reverse osmosis water device has an integrated carbon filter.

From the above list, you can quickly know what reverse osmosis systems remove from your house water.

In the multi-stage RO filtration process within the device, water can pass through pre-filters (to get rid of large particles, sediment, and chlorine smell) and the post-water filter (generally carbon filtering to enhance the taste).

For instance, in the case where fluoride is your primary concern, it is evident that a RO system can remove up to 92% of your water.

What Does not Reverse Osmosis Remove?

Certain pollutants are smaller in molecular size than water. Reverse Osmosis isn’t always the panacea that many believe it is in terms of giving water that’s clean of contaminants. 

Some of the most common contaminants that can pass through the typical RO filter include:

  • Pesticides
  • Herbicides
  • Other agricultural products such as fungicides
  • Some dissolved gasses, like hydrogen sulfide
  • Certain organic compounds
  • Chlorine RO can remove different amounts of chlorine. However, the typical home RO filter might not remove all chlorine in the water, although it will depend on the chemical concentration within the water supply.

Do I Require RO Filter to Have Pure Drinkable Water At Home?

Over the last 10-15 years, an alkaline water filtration system has been advertised as the best solution for drinking water at home when combined with activated carbon.

However, RO filters are generally an expense in terms of money and water for most households.

Before buying the best whole house RO system unit or additional purification equipment, make sure you check the quality of the tap water at home and the requirements to ensure it is delicious and safe.

What are the advantages (pros) of Reverse Osmosis filters? 

  • Proven technology ensures pure drinking water.
  • A better option for hard water treatment.
  • Produce high-quality tap water free from heavy metals, bacteria, and dissolved solids.
  • Ro water treatment system can improve water quality and gives clean water the same as bottled water.
  • Tap water can be made drinkable by making rich mineral levels (TDS 1500 or more ) drinkable.
  • RO water purifier protects the user from waterborne infections that can be harmful.
  • It can improve metabolism & digestion.
  • RO water treatment system can help improve the appearance of skin, hair, and losing weight.

What are the disadvantages (cons) of Reverse Osmosis filtration system?

  • The amount of waste produced is as high as six times the amount of pure water produced.
  • Requires professional support to ensure its effectiveness and security. 
  • It eliminates healthy minerals like potassium, magnesium, calcium, and bicarbonates, so you need to remineralize RO water.   
  • The cost is relatively high, starting at $300 plus maintenance and repairs.

Best Reverse Osmosis Filter Alternatives

Boiling Water

One of the most secure and efficient methods to get pure distilled water is boiling it. 

Since the beginning of time, boiling has been among the most widely used and traditional methods utilized in all households. It was first introduced long before reverse osmosis purifiers were created.

To boil, first, make sure that the water appears cloudy or clear. If not, put the water into the pot and set it on a gas or electric stove.

You need to heat water at high temperatures until it is boiling. If it appears to be cloudy, it could be contaminated with dirt. Therefore, you should clean the water using a paper towel or cloth before you boil it.

Water filter as many times as needed to ensure that the filter is working correctly. Cover the lid to ensure quicker boiling and less time since the lid assists in holding heat.

Please make sure the water is at a rolling boil to ensure that it is boiling accurately. Allow the steam to then churn for a few minutes.

 Let the distilled water cool before drinking.  

City Water Softener

Hard water can impact your daily routine in the long term! If you’re not sure what hard water is, it results from an excessive amount of minerals in your drinking water (magnesium and calcium).

It could cause ugly marks on your home appliances, block your pipes, and, even more importantly, could be a cause of irritation to your skin.

If you are experiencing hard water flowing through your pipes and looking for an easy solution, check out water softeners for your home.

These devices will remove the minerals that cause hardness, magnesium, and calcium from your water, making it safe for home use.

You may believe the water softener is too costly; however, that’s completely incorrect!

It’s true that the cost of water softeners is low, enough that the average family could quickly put it within their homes to get bottled water quality.

If you’re searching for a city water softener that will fit your home, ensure that the model you select can be installed quickly and has solid construction.

Purifying Through Chlorination

The process of purifying chemicals is used to purify water by adding chlorine tablets to the water.

Suppose the water appears cloudy; filter or strain it with a clean fabric or kitchen towel to get rid of the dirt. Also, make sure to verify the purity of the water before putting it into the chlorine.

The chlorination of water helps kill numerous harmful bacteria and pollutants. Put four drops of bleach in a liter of 8 drops each half gallon

Allow it to rest for at least half an hour to allow the water to be drinkable.

The minimum temperature of untreated water must not be lower than 16 degrees Celsius to effectively water chlorination.

The water may appear different; however, the great news is that it’s safe to drink.

Although chlorine is cheap and readily available, you should keep your eyes on the fact that too much chlorine may be harmful to your health, and you should remain cautious.

Additionally, with chlorine, you can’t guarantee the complete removal of all complex microorganisms found in water that is clear.

Iodine Water Purification

Another efficient and easy chemical purification option is using Iodine to purify water. Iodine is a powerful agent that kills all kinds of pollutants and microorganisms in water. 

In hot or room temperature water,  put five drops of Iodine in each liter of water that is clean. Add tiny drops of Iodine if the water appears cloudy.

Allow it to be at least 30 minutes before it’s safe to drink. Iodine can be more efficient when the temperature of the water is higher than 21 Celsius.

Because it is portable, it is ideal for traveling to locations where purified, filtered water isn’t readily available, like, when you camp in the wilderness and require pure drinking water.

But, it does not kill 100% of the pathogens that are present in water.

Additionally, Iodine can add some bitterness to the flavor of the water. If you are not a fan of its taste, you can try adding less than ten drops of Iodine to the water.

People who are sensitive to Iodine are not able to make use of this method for water purification.

The Myths and Truth of RO Water

Myth 1. RO purified water is unhealthy to drink

Some detractors claim that purified water is artificial and unhealthful and should be used only in industrial settings and not for consumption by humans. 

They claim that RO water isn’t pure and clean for it to count healthy because this kind of mineral-free, pure water isn’t found on the planet. However, this type of water exists and is known as RAIN.

The fact is that Reverse Osmosis removes impurities from the water that is clean and safe to drink. Research has proven that RO drinking water is pure with no adverse side effects over the more than 60 years of studies

RO technology has been extensively tested through the US military and has been widely utilized as drinking water for soldiers and civilians who serve in our military.

MYTH 2. RO takes healthy minerals out of water

RO systems can take out minerals from the tap water. However, humans acquire most of our minerals from the food we consume and in contrast to drinking water.

For instance, a glass of juice from an orange contains precisely the amount of mineral content as 30 gallons of tap water.

Additionally, you will receive more minerals from one vitamin tablet than by drinking a month’s filtered water supply.

According to WQA, in conjunction with the WHO, we get the bulk of the minerals we need from our food, not drinking water. Inorganic minerals present in water have little or no effect and can be highly harmful to our health.

Myth 3 RO removes minerals in the body.

House Reverse Osmosis water cannot remove minerals from human bodies. Water is the universal solvent since it constantly “wants” to have substances dissolve within it.

The more pure the water is, the more aggressive it is in attacking objects that can dissolve.

It doesn’t harm the human body since our physiology is quick to achieve homeostasis through saliva, stomach fluids, and other fluids to balance all bodily fluids.

There is no scientifically proven evidence that reverse osmosis-treated water could eliminate minerals from the human body.

Myth 4. RO wastes a lot of water

RO utilizes specific amounts of water to ensure durability and quality. For every gallon of pure water created by an RO system, the average is 4 Gallons of brine water being used up and then disposed of.

The brine (waste) liquid is utilized to cleanse the RO membrane, letting the filter work efficiently and lasting for years.  

In reality, many people use discarded water to utilize in watering plants and gardens or used to store and use in other household tasks.


Does reverse osmosis eliminate fluoride?

Reverse Osmosis can remove many harmful substances and fluoride from tap or brown well water

The system pumps water with a significant pressure over the membrane with tiny pores, which only permit the water to flow through it, thus preventing more significant pollutants (including fluoride) from moving further.

The tap water contaminated with pollutants, also known as wastewater, is removed from the system.

It happens at a steady pace characterized by water entering the chamber, then passing into the RO membrane, and then the wastewater flowing out through the drainpipe.

Because fluoride particles aren’t significant to pass across the semi permeable membrane, they’re eliminated from the system, along with most other contaminants in the tap water.

Can reverse osmosis remove bacteria and viruses?

RO membrane filter has pores of around 0.0001 microns. For illustration, bacteria like E. coli and salmonella are between 0.2 – 4 microns in diameter and are too big to pass into the pores.   

According to a study published in the CDC, Reverse Osmosis systems have very high efficiency in:

  • Get rid of protozoa (e.g., Giardia, Cryptosporidium)
  • Eliminating the bacteria (e.g., Salmonella, Shigella, Campylobacter, E. coli)
  • Remove viruses (e.g., Hepatitis A, Norovirus, Enteric, Rotavirus).

To return to the issue: Does reverse Osmosis remove bacteria and viruses? Yes, it does, and it works effectively for various contaminants and viruses transferred through water.

Beware of the misconception that RO technology cannot destroy bacteria and viruses. It just ensures that they’re removed, and you’ll be left with pure water.

Does reverse osmosis remove chlorine?

Yes! The reverse osmosis filtration system removes chlorine by passing it through several stages of filtering and making alkaline water in your home quickly. 

Standard filters found within an RO system include pre-filters, activated carbon filters, a reverse-osmosis membrane, and the post-filter.

If you’ve conducted any investigation on the removal of chlorine, it’s true that activated Carbon filters are extremely efficient in removing.

However, reverse Osmosis is more efficient since after a significant amount of chlorine has been removed from the activated carbon filtering process; water can flow across the semipermeable membrane with tiny pores; chlorine molecules cannot be big to be able to pass through. 

Does reverse osmosis remove iron?

Reverse Osmosis eliminates Lead, manganese salts fluoride, Iron, lead, and calcium (Binnie and al. 2002).

The majority of minerals found on water’s surface are larger than the water molecules in addition to the semi-permeable RO membrane can hold the minerals.

They are eliminated from drinking water after the water is cleansed by RO (AllAboutWater.org 2004).

Does reverse osmosis take salt out of the seawater?

Semi-permeable membrane permits the water that feeds it to flow more than the dissolving salts.

Reverse Osmosis devices function by applying pressure when freshwater flows through their membranes to eliminate the saline concentration in feed water and the minerals and other pollutants.

The impurities that are not wanted are removed, recycled, or processed. Reverse osmosis seawater systems employ multiple membranes to increase the amount of water purified that is released every day.


Reverse Osmosis System can remove the various harmful contaminant and provide freshwater across the globe in which water is scarce and for industrial cleaning of wastewater.

It could also be an effective solution to filter contaminants, dissolved solids, heavy metals, and household use in situations requiring it.

But, in the majority of instances, they consume municipal water. An activated carbon faucet filter can provide delicious and fresh tap water for less cost and lower waste.         

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